SAN FRANCISCO — The wayward Air Canada plane that nearly caused an aviation disaster at San Francisco International Airport last month dropped off radar displays for 12 seconds in the moments before it approached four fully loaded passenger jets on the taxiway, according to new information released Wednesday from federal aviation officials investigating the incident.

The Airport Surface Surveillance Capability (ASSC) system monitors incoming aircraft to ensure they are safely landing at SFO and 34 other airports across the country valor do bitcoin em dolar. The system, which provides a computerized visual to air traffic controllers, is designed to sound a warning from a loudspeaker in the tower if an airplane on final approach is heading for an occupied runway.

But it does not warn for planes that may be incorrectly aligned to land on a taxiway, as was the case for the Air Canada plane.

However, on July 7, when Air Canada Flight 759 mistook a crowded taxiway for its approved runway, nearly triggering one of the worst aviation disasters ever, the radar system offered no help.

Shortly before midnight that night, “the airplane flew too far right off course to be observed by the local controller’s ASDE-X/ASSC and was not visible on the ASDE-X/ASSC display for about 12 seconds,” the NTSB reported Wednesday.

A source familiar with the investigation called it a “blind spot” that is a half-mile from the start of Runway 28-Right and Taxiway C how do i buy bitcoin. The system, among other functions, uses the airport’s radar to follow incoming airplanes and is designed to warn controllers early enough in an approach so they can alert a plane of a possible collision.

It is difficult for air traffic controllers to determine from the tower whether airplanes are properly lined up on approach; however, the computer system can aid them, a source said.

Runways 28-Left and 28-Right and Taxiway C are parallel to each other bitcoin 2048. In post-incident interviews, the Air Canada flight crew told investigators that they believed the lighted runway they saw was 28-Left, and that Taxiway C was actually their cleared runway 28-Right how to make money using bitcoin. For more travel coverage from the San Francisco Bay Area and beyond

But runway 28-Left had been closed for maintenance and featured a giant lighted “X” to warn pilots, along with other advanced warnings sent to flight crews, according to SFO officials and the NTSB.

The captain has over 20,000 total flight hours; about 5,000 of those as a captain in Airbus 320-series planes bitcoin definition for dummies. The first officer has about 10,000 flight hours, more than 2,300 of those in Airbus aircraft.

NTSB investigators have not determined a probable cause for the incident, and the information released Wednesday does not contain analysis of the information, so no conclusions have been reached, the agency said.

NTSB preliminary findings and independent analysis of flight data show the Airbus 320 shortly before midnight on July 7 continuing its landing descent over two airplanes on the taxiway before finally climbing above two more planes awaiting departure bitcoin payout address. At its closest moment, the Air Canada flight was an estimated 51 feet above a fully loaded Philippine Airlines plane.

Federal investigators found that Air Canada was lined up to the taxiway starting at three miles out from the airport how to spend bitcoins. Around 0.7 miles out, the pilot warned of lights on the runway bitcoin goldman sachs. Six seconds later, Flight 759 dropped from radar.

As the plane was about 0.3 miles from the edge of the taxiway, the air traffic controller replied to the pilot’s concern over lights on the runway and affirmed the plane was cleared to land on runway 28-Right, not realizing the pilot was aimed at the taxiway localbitcoins paypal. A United Airlines pilot warned over the radio that Air Canada was lined up on the taxiway, and the Philippine Airlines crew, the second plane on the taxiway, turned on its landing lights to try to warn Air Canada about the errant landing, according to the report.

The Air Canada pilot powered up its thrust when it was about 85 feet above ground, but the plane had dropped as low as 59 feet before it began to climb bitcoin history graph. After the radar black-out, the tower picked up the Air Canada flight again on its displays when it was over the first airplane, according to the report.

The pilot had already begun to pull up when the air traffic controller ordered a “go-around.” Two air traffic controllers were on duty that night, but only one was working in the tower at the time of the incident, according to the NTSB. Stay up to date on breaking news with our mobile app from the Apple app store or the Google Play store.